Audio Visual Entrainment and Acupressure Therapy for Insomnia
Anne George, Oluwatobi Samuel Oluwafemi, Blessy Joseph, Sabu Thomas, Sebastian Mathew, V. Raji in Holistic Healthcare, 2017
The brain is made up of billions of brain cells called neurons, which communicate by means of electrical signals. The combination of millions of neurons sending signals at once produces an enormous amount of electrical activity in the brain, which can be detected using sensitive electrodes that measure electricity levels over areas of the scalp. The combination of electrical activity of the brain is commonly called a brainwave pattern, because of its cyclic, wave-like nature. Brainwaves are divided into bandwidths to describe their function but are best thought of as a continuous spectrum of consciousness. The brainwaves change according to actions and emotions. When slower brainwaves are dominant one may feel tired, slow, or dreamy. The higher frequencies are dominant when one feels active or alert. The brainwaves are classified based on frequency as alpha, beta, theta, and delta. They are depicted in Figure 10.1.
Disruptions in physical substrates of vision following traumatic brain injury
Mark J. Ashley, David A. Hovda in Traumatic Brain Injury, 2017
There are two types of brain cells, neurons and neuroglial cells. The major types of neuroglial cells in the gray matter are astrocytes, oligodendrocytes, and microglial cells. Astrocytes form the building blocks of the blood-brain barrier, help to create an extracellular space to clean toxins and waste products, remove excessive neurotransmitters from synapse, refuel the brain at night to provide energy and secrete neurotropic factors. Astrocytes’ main role is to maintain neuronal function. Oligodendrocytes produce myelin to insulate axons, produce all brain cholesterol, and have a very high metabolic rate, replicating themselves throughout life. Microglial cells are the resident macrophages of the central nervous system, protecting the brain through neuroinflammatory responses. The obvious difference between neurons and neuroglial cells is the latter do not have axons or dendrites or produce action potentials.
Coma and Disorders of Consciousness
Alexander R. Toftness in Incredible Consequences of Brain Injury, 2023
For a person to be conscious—awake and aware—communication between widely spread out brain areas is needed. Because such a wide area of the brain is involved, many kinds of damage can be disruptive to consciousness. Comas and disorders of consciousness can result from a wide variety of issues, including drugs or poisons, lack of oxygen, strokes, traumatic brain injuries, degenerative diseases, and many others (Multi-Society Task Force on Persistent Vegetative State, 1994). The brain damage for people with different disorders of consciousness may vary widely, but an overall description of what the brain is experiencing is reduced intracortical modulation. What this means is that brain cells are not exciting and inhibiting each other in the typical way that brain cells communicate (Bagnato et al., 2012). The brain is less active in disorders of consciousness, and brain activity doesn't spread or follow patterns like it usually does. Both wakefulness and awareness depend on the interaction between the cerebral cortex and the reticular system (Bleck, 2003).
The Need for Guidance around Recruitment and Consent Practices in Intracranial Electrophysiology Research
Published in AJOB Neuroscience, 2021
The US BRAIN Initiative which seeks to advance innovative technologies aimed at revolutionizing understanding of the human brain, has created a surge in intracranial electrophysiological research. For example, the BRAIN Initiative funding call Research Opportunities Using Invasive Neural Recording and Stimulating Technologies in the Human Brain focuses on maximizing “opportunities to conduct innovative in vivo neuroscience research made available by direct access to brain recording and stimulating from invasive surgical procedures.” These studies recruit patients undergoing neurosurgical procedures for conditions such as epilepsy, brain tumors and Parkinson disease. Such studies “provide unique opportunities to record high-resolution signals in vivo from the human brain—data that are otherwise unavailable”—enabling the exploration of brain function at the level of single brain cells or small cellular assemblies, and additionally enabling the advancement of neuroscientific knowledge related to brain health (Mukamel and Fried 2012).
Genetic effects of non-ionizing electromagnetic fields
Published in Electromagnetic Biology and Medicine, 2021
Regarding cell-type specificity, one can speculate that: 1. Cells that are metabolic active are more susceptible to EMF effects with an increase in generation of free radical in the mitochondria; 2. Cells that have higher anti-oxidative activities are less susceptible; 3. Transitional elements, e.g., iron, may play a role in the effect via the Fenton reaction (see Lai, 2019). Brain cells contain a relatively high concentration of free iron, particularly intercalated in the DNA molecules, and are more susceptible; 4. Cell cycle arrests are common in cells exposed to EMF. It may be a response to repair genetic damages caused by EMF. If damage could not be repaired, cell death occurs, particularly via apoptosis, which is a common outcome after EMF exposure. These effects are consistent with the gene expression studies, showing activation of genes involved in both cell death and repair. 5. If genetic damaged cells are allowed to survive, cancer may occur. However, if they die, the risk of cancer would actually be reduced. But, other detrimental health outcomes may occur, e.g., death of brain cells could lead to neurodegenerative diseases. Increased incidences of degenerative diseases (including Alzheimer’s disease, amyotrophic lateral sclerosis, dementia, and motor dysfunctions) after EMF exposure, particularly under occupational conditions, have been reported (Gervasi et al. 2019; Gunnarsson and Bodin 2018, 2019; Huss et al. 2018; Koeman et al. 2017; Jalilian et al. 2018; Pedersen et al. 2017; Sorahan and Mohammed 2014).
The changes of systemic immune responses during the neuroprotection induced by remote ischemic postconditioning against focal cerebral ischemia in mice
Published in Neurological Research, 2019
Cuiying Liu, Jian Yang, Chencheng Zhang, Xiaokun Geng, Heng Zhao
Until now, the irreversible damage of brain cells after stroke is still a major cause of death and disability in adults worldwide [1]. The main revascularization therapies for acute ischemic stroke are thrombolysis with recombinant tissue plasminogen activator and endovascular thrombectomy [2]. However, later reperfusion after revascularization therapy can trigger deleterious processes and lead to more worsening outcomes[3]. Therefore, much attention has been paid to neuroprotective mechanisms that could prevent brain injury caused by ischemia and reperfusion [4,5]. Remote limb ischemic postconditioning (RIPostC), which is performed in the hind limbs, has been reported to protect against heart and brain ischemia [6,7]. RIPostC may have a greater potential than conventional ischemic postconditioning because of its lower risk treatment.
Related Knowledge Centers
- Glia
- Interneuron
- Membrane Potential
- Stroma
- Synapse
- Blood Vessel
- Brain
- Neuron
- Neural Circuit
- Large-Scale Brain Network